Science & Mathematics - 30 September 2007

2007-09-30 11:33:36 · 3 answers · asked by sid 1 in Botany

logically, where does the rule come from?

2007-09-30 11:32:28 · 4 answers · asked by Anonymous in Mathematics

A bag contains red, white, and blue marbles of which 2/3 of the marbles are blue. If there are 1/3 as many red marbles as blue, and there are 20 white marbles in the bag, how many marbles are in the bag?


A. 60
B. 100
C. 120
D. 140
E. 180


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If a and b are different prime numbers greater than 2, and n = a x b, then how many positive factors, not including 1 and n, does n have?

A. 0
B. 1
C. 2
D. 3
E. 4

2007-09-30 11:31:46 · 2 answers · asked by Anonymous in Mathematics

it has to to with logarithmic tables

like with star brightness, they'll say the light was on an order of magnitude five times any other, which means it's a hundred times brighter

10 squared is 100, I don't get this

2007-09-30 11:31:03 · 1 answers · asked by SQD 2 in Physics

2007-09-30 11:29:39 · 1 answers · asked by desidude420 1 in Chemistry

I am Russian, but I have lived in the US for most of my life. Is it just me or is it pathetic that Russia is betting the US in the space race, even though they have many, many times less funding?

2007-09-30 11:29:34 · 6 answers · asked by Eugene 2 in Astronomy & Space

2007-09-30 11:29:13 · 3 answers · asked by Anonymous in Engineering

The active agent in many hair bleaches is hydrogen peroxide. The amount of hydrogen peroxide in 17.0 g of hair bleach was determined by titration with a standard potassium permanganate solution.
2 MnO4-(aq) + 5 H2O2(aq) + 6 H+(aq) 5 O2(g) + 2 Mn2+(aq) + 8 H2O(l)

(a) How many moles of MnO4- were required for the titration if 43.4 mL of 0.109 M KMnO4 was needed to reach the end point?
mol
(b) How many moles of H2O2 were in the sample?
mol

2007-09-30 11:28:11 · 2 answers · asked by cj 2 in Chemistry

2007-09-30 11:28:10 · 2 answers · asked by exxohh<3 1 in Biology

im doing a life science project, and for my leaves and wildflowers i have to alphabatize them by genus...what does that mean?

2007-09-30 11:27:19 · 3 answers · asked by Anonymous in Botany

2007-09-30 11:26:37 · 13 answers · asked by Wendla 1 in Zoology

which of these 3 choices are right....i kinda eliminate the others that i think is not right...but i could be wrong...

A) y(lnx+1)
B) xy (2lnx+1)
C) -y (2lnx-1)

2007-09-30 11:26:04 · 2 answers · asked by ph103 1 in Mathematics

what is this called?

2007-09-30 11:25:37 · 10 answers · asked by Jen Bug <3 2 in Physics

2007-09-30 11:25:16 · 3 answers · asked by Anonymous in Mathematics

Can you suggest a good name for an alien galaxy, planet, species, and a few names of the alien citizens!

Thanks!

2007-09-30 11:24:55 · 9 answers · asked by Anonymous in Astronomy & Space

5-12(2-x)=6

3-7d=5d+4

5x-2(2-x)=9-(4x+2)

SHOW ALL WORK

2007-09-30 11:21:48 · 10 answers · asked by Indie 2 in Mathematics

is the plant white top native to the united states or not!!!!if it is where does it come from????

2007-09-30 11:19:29 · 2 answers · asked by Angel♥ 1 in Botany

-microwaves.

-ultraviolet rays.

-a blackbody spectrum.

-gamma rays.

-infrared rays.

2007-09-30 11:17:39 · 2 answers · asked by 1337Haxor 2 in Chemistry

1. Write an equation for the dissociation of the following ionic compound when it dissolved in water Al2(SO4)3.
A. Al2(SO4) 3 (s) --> Al2+(aq) + SO43-(aq)
B. Al2(SO4) 3 (s) --> 2Al (aq) + 3SO43-(aq)
C. Al2(SO4) 3 (s) --> Al3+(aq) + SO42-(aq)
D. Al2(SO4)3(s) --> 2Al3+(aq) + 3SO42(aq)

23. How many grams of strontium nitrate Sr( NO3)2 would you need to prepare 2.00 L of a 0.400M solution of strontium nitrate?
A. 125 g
B. 169 g
C. 210 g
D. 299 g

24. What mass of methanol, CH3OH, must be dissolved to make 1.50 L of a 0.675M solution?
A. 4.5 g
B. 13.8 g
C. 22.1 g
D. 32.4 g

25. What is the molarity of a solution that contains 17.2 g of lithium perchlorate, LiClO4, in 2250 mL of solution?
A. .00760M
B. .0719M
C. .815M
D. 1.2M

2007-09-30 11:15:56 · 4 answers · asked by Anonymous in Chemistry

A child riding a bicycle at 15 meters per second decelerates at the rate of 3.0 meters per second squared for 4.0 seconds. What is the child's speed at the end of 4.0 seconds?

2007-09-30 11:14:34 · 2 answers · asked by xenycexgurlx 1 in Mathematics

2007-09-30 11:13:16 · 7 answers · asked by Victor D 2 in Astronomy & Space

The Sine of -3x, Looks like this Sin(-3x). When I put it in my calculator, it gives me a reflection over the x axis. So does -sinx = Sin(-x) ???

2007-09-30 11:09:23 · 1 answers · asked by Anonymous in Mathematics

Which of the following statements are true for the 5f sublevel ?

a) n = 4

b) n + l = 8

c) l = 4

d) There are eight possible orbitals

e) There can be a maximum of eighteen electrons

f) There can be a maximum of eight unpaired electrons

2007-09-30 11:08:47 · 1 answers · asked by Anonymous in Chemistry

a) How many electrons in an atom can have the designation 6d ?

b) Which orbital has the following quantum numbers?

n = 3 minimum value of ml = -1

2007-09-30 11:08:10 · 1 answers · asked by Anonymous in Chemistry

This is a data chart of a groups bridge-thickness

Bridge Thickness (layers)1 2 3 4 5 6
Breaking Weight(pennies)22 32 40 57 68 84

Predict the breaking weight of a bridge made from 14 layers. Show all work.

PLEASE HELP I CANT FIGURE IT OUT!

2007-09-30 11:07:37 · 3 answers · asked by Indie 2 in Mathematics

How many sections make up the conics field of analytical geometry? Also, is locus geometry part of conics? If so, in what way?

2007-09-30 11:05:07 · 2 answers · asked by journey 1 in Mathematics

Physics Experts Help! Ok A stick of butter has a volume of 120cmcubed and a mass of 110g. What is the volume?
A stick of butter has a volume of 120cmcubed and a mass of 110g. Explain reasoning for each step

A.What is the volume of 1g of butter?
B. What is the volume of 6g of butter?
C.What is the mass of 50cmcubed of butter?
QUESTION 2
the density of silver is 10.5g/cmcubed
A. What is the mass of 7cmcubed of silver
B. What is the volume of 64g of silver
C. How many 1cmcubed pieces of silver must be combined to have a total mass of 64g
D. How are questions B and C related?

Question 3
One cubic centimeter of copper has a mass of 8.9G What is the volume of a piece of copper with a mass of 1.23 KG?

Question 4
Suppose we have a piece of lead with a mass of 70g. How much will the volume of lead increase if we add 30g more lead to this piece? Lead has a density of 11.3g/cmcubed

2007-09-30 11:04:50 · 1 answers · asked by ????? ? 1 in Physics

group number- family name

2007-09-30 11:04:32 · 1 answers · asked by Anonymous in Chemistry

A car traveling at a constant speed of 45.0m/s passes a trooper hidden behind a billboard. One second after the speeding car passes the billboard, the trooper sets out in pursuit to catch it. The trooper accelerates at 3.00m/s^2 from rest. How long will it take the trooper to overtake the car?

2007-09-30 11:03:59 · 1 answers · asked by Anonymous in Physics

2007-09-30 11:03:47 · 8 answers · asked by M2 1 in Mathematics